Code Signing (JDK 1.1)

Code signing is a security measure which you can use to identify the originator of a downloaded class. The m-let service will enforce code signatures if it is instantiated in secure mode. One of the constructors of the MLetSrv class takes a boolean parameter which specifies the security mode. For obvious security reasons, the security mode cannot be modified once the m-let service is instantiated.

When the m-let service is running in secure mode, it will only load classes and native libraries which are signed by a trusted party. A trusted party is identified by a key: this key was used to sign the code and a copy of the key is given to all parties that wish to download the signed class. Therefore, you must identify trusted keys in your agent before attempting to download their signed classes.

Downloading native libraries always requires a custom security manager, regardless of whether they are trusted or not. See the description of the "Security Manager (JDK 1.1)".

In the JDK 1.1 environment, .jar files are signed using the javakey utility. You also use the javakey utility on your agent's host to identify trusted keys. The command line parameters of this tool allow you to define your security policy based on trusted identities and keys. Please refer to the JDK documentation of the javakey utility for details.

When the secure mode of the m-let service is enabled, unsigned classes and libraries will never be loaded.

When the secure mode is not enabled, all classes and native libraries may be downloaded, regardless of whether they are signed and not trusted, or not signed.